1. Field of the Invention
The present invention relates to a slide switch having an operational member slidable in a direction along a virtual plane, a plurality of movable contacts arranged at positions surrounding the operational member and a plurality of fixed contacts provided in correspondence with the movable contacts so as to render at least one of the movable contacts into a conductive state in association with a sliding operation of the operational member.
2. Description of the Related Art
Techniques relating to a slide switch having the above-described construction are known from Patent Document 1 and Patent Document 2 identified below.
Patent Document 1: Japanese Patent Application “Kokai” No. 7-262878
Patent Document 2: Japanese Patent Application “Kokai” No. 2003-31076
With the switch disclosed in Patent Document 1, a contact switching shaft of an operational button (corresponding to “operational member” of the present invention) is inserted into a cross-shaped aperture defined in an operational button guide panel, and at positions surrounding this switching shaft, there are disposed four first contacts (corresponding to “movable contacts” of the present invention) and corresponding second contacts (also corresponding to “movable contacts” of the present invention). In this switch, as the four first contacts cooperate to exert an elastic urging force to clamp the switching shaft, the operational button is urged toward its neutral position. When a user operates the operational button, the contact switching shaft is pressed against a first contact corresponding to the operated direction, so that this first contact is placed into contact with the second contact, thereby obtaining a conductive state.
With the switch disclosed in Patent Document 2, inside a main case, there is disposed an urging member formed of elastomer and having four projections. At the center portion of this urging member, there is embedded a sliding member, to which an operational button is operably connected. In this switch, four conductive members (corresponding to the “movable contacts” of the present invention) are provided in the outer periphery of the urging member and electrodes (corresponding to the “fixed contacts” of the present invention) are provided in the inner wall of the main case at positions thereof corresponding to the conductive members. Under an un-operated state, the operational button is urged to its neutral position by the urging force from the urging member. When the operational button is operated, the conductive member is contacted therewith to render an electrode into a conductive state.
Further, with this switch, a slider is fitted on the opposite side to the operational button and a movable contact is disposed at a position contactable with this slider. And, a fixed contact is disposed at a position corresponding to this movable contact. The movable contact has a center portion projecting toward the slider. When the operational button is operated in a depressing direction, the movable contact is elastically deformed to come into contact with the fixed contact, thus establishing electric conduction.
With this type of slide switch, a good operational feel can be obtained if the operational member thereof can be slid smoothly under a stable posture. And, such good operational feel should be maintained also in the case of the operational member being operated by its depression, as described in Patent Document 2.
However, in the case of the switch disclosed in Patent Document 1, when the operational button is slid, this operational button comes into contact with the operational button guide panel, so that the button can be operated smoothly. On the other hand, however, as the operational button guide panel is exposed to the outside, such smooth operation can be impaired if dust or the like enters the panel.
Further, in the case of the switch disclosed in Patent Document 2, the sliding member is engaged with the slider which effects a sliding operation in directions normal to each other. Hence, during a sliding operation, the sliding operations need to take place at a plurality of contact faces, so that this fact may impair the smooth sliding operation.